ASOBono

This is THE place to take your small kids and to let them run buck wild with minimal supervision from parents. I don’t see why every parent doesn’t bring their kids here to burn some child energy off for a while. There are a ton of physical activities for kids to do, such as a big air trampoline, a giant plastic ball pool, jungle gyms, pretend restaurants, puzzles, books, everything except video games (which is awesome). Also, every once in a while, a staff member will come out and lead the kids in an interactive activity with some songs and rhymes. Kids will interact with other kids and they are encouraged to scream, run, and generally have fun. I brought my nieces here and by the time they were done, they were passed out.
You can pay by the hour here or you can get a day pass for 1500Yen (about $ 13) which is what I did. There are some weekdays with specials too.
Just a warning: On rainy days, this place is packed!

Gem got a little ambitious on our trip to Tokyo and had this whole list of places that she wanted to see/​do/​etc. ASOBono was one of them. Funny thing is that we stumbled across this place after getting off the train station. We had planned to go to Tokyo Dome and didn’t realize that it’s all in the same place. Dome, roller coasters, restaurants, theme parks, etc — all in one walkable space. We saw the signs for ASOBono and before I could even run to the restroom Gem was already getting a locker for us. This place is huge, clean and bright. It looks small when you first walk in and then you come across the ball pit that takes up more than half of the first room. There’s a whole other room that’s just small toy cars and tracks (Tomica is huge out here), another room for pretend grocery shopping, cooking, etc., a library, there was a boat with fishing poles and I feel like we didn’t even get to see the entire space. Best part, they close off sections to clean. Really clean. So I got ahead of myself but how this place works is you pay for your child and I believe it includes an adult. Each adult is an extra charge. You pay by the hour or longer if you want. We got here very late and opted for the one hour — which was more than enough. If you have a stroller, they have stroller parking with locks to secure your stroller! They have lockers that you can store your belongings and they advise you to not take personal items into the play area. I can’t imagine looking for anything in that ball pit. Btw, Gem almost broke her wrist going down the wall slide that said don’t go down this area. I thought I’d point that out. lol. We thought it would be impossible to get Logan out of this place but the had a small gift shop right next to the exit and promised Logan we’d get him something (yes bribery works) on the way out. I’d definitely come back to this place if I was in the area and highly recommend it to any family.

Took my toddler here while on vacation. What a huge place! You could spend hours here! There’s so much to do. The biggest is the huge playground/​ball pit. There’s a huge train/​Lego room. There’s also rooms that have various themes such as library, market, baby dolls etc. price was reasonable considering how much stuff there is to do. We only bought an hour (it’s based on the honor system since there wasn’t anything saying when to leave)